1. Field of the Invention
This invention relates to an apparatus for the separation of finely divided and/or dissolved substances and solids out of liquids, especially water, in which the liquid to be purified flows through a treatment column filled with filtering and/or adsorbing material.
Such apparatuses, hereinafter referred to merely as "adsorber installations" for the sake of simplicity, which can contain adsorbing and/or filtering substances, serve by way of example for the purification of industrial waters, drinking water, surface water, bath water, cooling water, generally for the purification of waters fit for use. Further fields of use of such installations are the prepurification stages of industrial, rinsing or other waters which are worked up further in subsequent stages by conventionally or continuously working ion exchanger installations.
2. Description of the Prior Art
The dirt-absorption capacity and thus the working time of filters of conventional construction is limited, especially in the case of filtration of liquids having a high proportion of solids or suspended substances. The interruption of operation of such filter plant for the purpose of cleaning, that is back rinsing, is especially troublesome if the working up of the water by means of ion exchanger installations takes place continuously or almost continuously, that is where the regeneration and rinsing of the ion exchanger masses is effected outside the treatment column and the freshly regenerated ion exchanger mass is returned in the cycle into the treatment column. In this case in fact there is no interruption of operation for the purpose of regeneration of the ion exchanger masses, as in the conventional methods. In order to avoid an interruption of operation when using filter installations, hitherto with such a continuous manner of operation it was necessary to set up at least two filter assemblages so that in the case of back-rinsing of the one working filter the other filter held in reserve could be put into use.
In the conventional processes charged adsorber material must be replaced by a fresh filling since it is no longer usable. If the adsorbed materials are for example tensides, aliphatic or aromatic compounds, complete removal of the gathered organic substances is not possible. For this reason use is made of special process by treatment with solvents. The consumption of solvents amounts to about 1.5 to three times the volume of the adsorber material. In the case of a filter containing for example 200 liters of adsorber material, in the former processes it is necessary to wash with the minimum of about 300 liters of solvents, so that in the case of large units the treatment is very expensive. It can also be seen that the handling of such large quantities of solvents is expensive on account of the amount of apparatus required to be used and is problematical on account of the necessary protective measures.